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Re: Five fair coins are tossed one after the other. What is the probabilit
[#permalink]
06 Oct 2021, 09:27
1
Carcass wrote:
Five fair coins are tossed one after the other. What is the probability that only the first three are heads?
A. 1/32 B. 1/8 C. 5/16 D. 1/2 E. 11/16
P(HHHTT) = P(heads on toss 1 AND heads on toss 2 AND heads on toss 3 AND tails on toss 4 AND tails on toss 5) = P(heads on toss 1) x P(heads on toss 2) x P(heads on toss 3) x P(tails on toss 4) x P(tails on toss 5) = 1/2 x 1/2 x 1/2 x 1/2 x 1/2 = 1/32